Agricultural tool bars have been used for various purposes, such as for mounting various types of tillage tools including chisels and cultivators. In recent years, the tool bar has been advantageously used to mount single row planter units wherein the planter units can be adjusted to different row spacings. Foldable tool bars of this type are shown in previously issued U.S. Pat. Nos. 4,030,551; 4,116,282; 4,074,766; 4,046,203; and 3,941,194. In providing a foldable tool bar for planter units, it has been found to be particularly desirable to maximize the tool mounting space on the tool bar so as to permit the planter units to be adjusted to different row spacings. Heretofore, it has been a common practice to provide support brackets for folding wings of tool bars which extend upwardly therefrom so that when the wings are folded to their transport positions they will come to rest against the brackets. Such brackets reduce space on the tool bar which would otherwise be available for mounting and repositioning cultivator or planter units.
In some field operations, particularly planting, it is desirable to use a retractable land marker. Typically such markers are raised and lowered between transport and working positions by a linear hydraulic actuator interposed between the marker and the outer outboard end of the tool bar. Heretofore, it has been customary, when using such a hydraulically operated row marker, to run hydraulic hoses from the source of fluid pressure on the draft tractor along the exterior of the tool bar sections to the marker actuator. In this condition the hoses are unprotected and produce a cluttered appearance.
This invention is directed toward eliminating use of support brackets on the exterior of tool bars and providing instead a restraining mechanism for a folding tool bar wing which does not occupy space on the exterior of the tool bar. It is also an object of this invention to run the hydraulic hoses to the marker actuators by way of the interior of hollow tool bar sections and to use the restraining mechanism as means for protecting the hoses from damage at the folding connection between sections of the tool bar.